Cellular Manifestations Research Articles

Upregulation of NFE2L1 reduces ROS levels and α-synuclein aggregation caused by GBA1 knockdown

Biallelic mutations in the GBA1 gene result in Gaucher disease (GD), and both patients with GD and carriers of a single GBA1 mutation have an increased susceptibility to Parkinson's disease (PD), but the underlying mechanisms of this association are not yet clear. In previous studies, we established Gba1 F213I point mutation mice and found that homozygous Gba1 F213I mutant mice died shortly after birth, while heterozygous mice could survive normally. In this study, we investigated the transcriptomic changes in the brain tissue of Gba1 F213I heterozygous mice, identifying 138 differentially expressed genes. Among them, Nfe2l1 was the most significantly downregulated gene. Inhibition or knockdown of GBA1 in BE(2)-M17 cells resulted in decreased expression levels of NFE2L1. Knockdown of GBA1 or NFE2L1 could lead to an elevation in intracellular aggregation of α-synuclein (α-syn) and reactive oxygen species (ROS) levels, while upregulation of NFE2L1 effectively mitigated those cellular manifestations induced by GBA1 knockdown. In summary, our in vitro results showed that upregulation of NFE2L1 may provide a therapeutic benefit for cellular phenotypes resulting from GBA1 knockdown, providing new insights for future research on GD and GBA1-associated PD.

BioDeepfuse: a hybrid deep learning approach with integrated feature extraction techniques for enhanced non-coding RNA classification

ABSTRACT The accurate classification of non-coding RNA (ncRNA) sequences is pivotal for advanced non-coding genome annotation and analysis, a fundamental aspect of genomics that facilitates understanding of ncRNA functions and regulatory mechanisms in various biological processes. While traditional machine learning approaches have been employed for distinguishing ncRNA, these often necessitate extensive feature engineering. Recently, deep learning algorithms have provided advancements in ncRNA classification. This study presents BioDeepFuse, a hybrid deep learning framework integrating convolutional neural networks (CNN) or bidirectional long short-term memory (BiLSTM) networks with handcrafted features for enhanced accuracy. This framework employs a combination of k-mer one-hot, k-mer dictionary, and feature extraction techniques for input representation. Extracted features, when embedded into the deep network, enable optimal utilization of spatial and sequential nuances of ncRNA sequences. Using benchmark datasets and real-world RNA samples from bacterial organisms, we evaluated the performance of BioDeepFuse. Results exhibited high accuracy in ncRNA classification, underscoring the robustness of our tool in addressing complex ncRNA sequence data challenges. The effective melding of CNN or BiLSTM with external features heralds promising directions for future research, particularly in refining ncRNA classifiers and deepening insights into ncRNAs in cellular processes and disease manifestations. In addition to its original application in the context of bacterial organisms, the methodologies and techniques integrated into our framework can potentially render BioDeepFuse effective in various and broader domains.

Electrical signalling and plant response to herbivory: A short review

ABSTRACTFor a long time, electrical signaling was neglected at the expense of signaling studies in plants being concentrated with chemical and hydraulic signals. Studies conducted in recent years have revealed that plants are capable of emitting, processing, and transmitting bioelectrical signals to regulate a wide variety of physiological functions. Many important biological and physiological phenomena are accompanied by these cellular electrical manifestations, which supports the hypothesis about the importance of bioelectricity as a fundamental ‘model’ for response the stresses environmental and for activities regeneration of these organisms. Electrical signals have also been characterized and discriminated against in genetically modified plants under stress mediated by sucking insects and/or by the application of systemic insecticides. Such results can guide future studies that aim to elucidate the factors involved in the processes of resistance to stress and plant defense, thus aiding in the development of successful strategies in integrated pest management. Therefore, this mini review includes the results of studies aimed at electrical signaling in response to biotic stress. We also demonstrated how the generation and propagation of electrical signals takes place and included a description of how these electrical potentials are measured.

Mathematical model for BCG-based treatment of type 1 diabetes

This work introduces the first model of immunotherapy treatment, namely the Bacillus Calmette-Guerin (BCG) vaccine, for Type 1 Diabetes (T1D). The model takes into consideration the interaction network between multiple immune cell types and compartments. A set of ordinary differential equations (ODEs) is introduced to capture the connectivity between these variables and the clinical presentation of the disease. Four subsets of the T1D mice and healthy controls that exhibit normal and high-level glucose consumption are evaluated using the proposed model. Numerical results obtained for mice suggest that BCG treatment of the T1D patients that follow healthy eating habits normalizes glucose to levels observed in non-diabetic controls. Furthermore, glucose consumption profoundly influences disease progression. This outcome suggests that immunotherapy may modulate molecular and cellular manifestations of the disease but it does not eliminate T1D. Of note, our data, obtained from numerical simulations, indicate that the BCG immunotherapy treatment may benefit healthy controls on a high-glucose diet and can be used as a tool for further clinical investigation of BCG usage to control T1D.

Recent insights into the networking of CLN genes and proteins in mammalian cells.

Ceroid lipofuscinosis neuronal (CLN) genes encode 13 proteins that localize throughout the endomembrane system to regulate a variety of cellular processes. In humans, mutations in CLN genes cause a devastating form of neurodegeneration called neuronal ceroid lipofuscinosis (NCL), commonly known as Batten disease. Each CLN gene is associated with a specific subtype of the disease that differ from each other in severity and age of onset. The NCLs affect all ages and ethnicities worldwide but primarily affect children. The pathology underlying the NCLs is poorly understood, which has prevented the development of a cure or effective therapy for most subtypes of the disease. A growing body of literature supports the networking of CLN genes and proteins within cells, which aligns with the broadly similar cellular and clinical manifestations among the different subtypes of NCL. Here, all relevant literature is reviewed to provide a comprehensive overview of our current understanding of how CLN genes and proteins are networked in mammalian cells with an aim toward revealing new molecular targets for therapy development. Intriguingly, CLN gene and protein networking extends beyond the NCLs as recent work has linked several CLN genes and proteins to other forms of neurodegeneration such as Alzheimer's disease and Parkinson's disease. Thus, a deeper understanding of the pathways and cellular processes impacted by mutations in CLN genes will not only strengthen our knowledge of the pathological mechanisms underlying the NCLs but may also provide new insight into related forms of neurodegeneration.

EPIGENETIC ALTERATIONS IN GENE EXPRESSION IN THE AGING IMMUNE SYSTEM

Immunosenescence or aging of the immune system is characterized by dysregulation of the innate and adaptive immune system mechanisms, associated with a systemic low-grade inflammation (i.e., «inflammaging»), non-effective protective humoral and cellular immune responses to a microorgamis or vaccine, autoimmunity, and cancer. In addition, genetic dysregulation and alterations across the immune system drive the cellular manifestations of immunosenescence. In this narrative review, we provide an overview of the recent advancements in immunosenescence research concerning epigenetics alterations in gene regulation and disturbances in gene expression in the aging immune system, focusing on DNA methylation, histone modifications, and microRNAs.

The Redox Protein High-Mobility Group Box 1 in Cell Death and Cancer.

Significance: As a redox-sensitive protein, high-mobility group box 1 (HMGB1) is implicated in regulating stress responses to oxidative damage and cell death, which are closely related to the pathology of inflammatory diseases, including cancer. Recent Advances: HMGB1 is a nonhistone nuclear protein that acts as a deoxyribonucleic acid chaperone to control chromosomal structure and function. HMGB1 can also be released into the extracellular space and function as a damage-associated molecular pattern protein during cell death, including during apoptosis, necrosis, necroptosis, pyroptosis, ferroptosis, alkaliptosis, and cuproptosis. Once released, HMGB1 binds to membrane receptors to shape immune and metabolic responses. In addition to subcellular localization, the function and activity of HMGB1 also depend on its redox state and protein posttranslational modifications. Abnormal HMGB1 plays a dual role in tumorigenesis and anticancer therapy (e.g., chemotherapy, radiation therapy, and immunotherapy) depending on the tumor types and stages. Critical Issues: A comprehensive understanding of the role of HMGB1 in cellular redox homeostasis is important for deciphering normal cellular functions and pathological manifestations. In this review, we discuss compartmental-defined roles of HMGB1 in regulating cell death and cancer. Understanding these advances may help us develop potential HMGB1-targeting drugs or approaches to treat oxidative stress-related diseases or pathological conditions. Future Directions: Further studies are required to dissect the mechanism by which HMGB1 maintains redox homeostasis under different stress conditions. A multidisciplinary effort is also required to evaluate the potential applications of precisely targeting the HMGB1 pathway in human health and disease. Antioxid. Redox Signal. 39, 569-590.

The redox protein HMGB1 in cell death and cancer.

As a redox-sensitive protein, high-mobility group box 1 (HMGB1) is implicated in regulating stress responses to oxidative damage and cell death, which are closely related to the pathology of inflammatory diseases, including cancer. HMGB1 is a non-histone nuclear protein that acts as a DNA chaperone to control chromosomal structure and function. HMGB1 can also be released into the extracellular space and function as a damage-associated molecular pattern protein during cell death, including during apoptosis, necrosis, necroptosis, pyroptosis, ferroptosis, alkaliptosis, and cuproptosis. Once released, HMGB1 binds to membrane receptors to shape immune and metabolic responses. In addition to subcellular localization, the function and activity of HMGB1 also depends on its redox state and protein posttranslational modifications. Abnormal HMGB1 plays a dual role in tumorigenesis and anticancer therapy (e.g., chemotherapy, radiation therapy, and immunotherapy) depending on tumor types and stages. A comprehensive understanding of the role of HMGB1 in cellular redox homeostasis is important for deciphering normal cellular functions and pathological manifestations. In this review, we discuss compartmental-defined roles of HMGB1 in regulating cell death and cancer. Understanding these advances may help us develop potential HMGB1-targeting drugs or approaches to treat oxidative stress-related diseases or pathological conditions. Further studies are required to dissect the mechanism by which HMGB1 maintains redox homeostasis under different stress conditions. A multidisciplinary effort is also required to evaluate the potential applications of precisely targeting the HMGB1 pathway in human health and disease.

Abstract IA002: Inherited DNA repair defects and premature aging

Abstract Fanconi anemia (FA), a DNA repair disorder, is the most frequently inherited bone marrow failure (BMF) syndrome. Patients with FA suffer from early childhood onset of BMF, developmental abnormalities, and heightened susceptibility to solid tumors. FA patients also have a strong predisposition to myelo- dysplastic syndrome (MDS) and acute myeloid leukemia (AML). FA is caused by biallelic mutations in one of 23 FANC genes, whose protein products cooperate in the FA/BRCA DNA repair pathway and regulate cellular resistance to DNA cross-linking agents. Because of their underlying DNA repair defect, FA cells exhibit chromosomal instability and hypersensitivity to genotoxic DNA cross-linking agents, such as mitomycin C (MMC). FA bone marrow (BM) HSPCs are also hypersensitive to oxidative stress and inflammatory cytokines. FA patients and FA cells exhibit many features of Premature Aging. FA patients develop BMF because of HSPC exhaustion. Progressive age-related attrition is observed in CD34+ cell content in FA patients. Additionally, FA patients and FA mice exhibit HSPC functional defects. BMF in FA results from accumulation of DNA damage in HSPCs caused by endogenous cross-linking agents or physiological stress. In response to genotoxic stress, FA HSPCs hyperactivate growth-suppressive pathways, such as the p53 pathway (Ceccaldi et al, Cell Stem Cell, 2012) and the transforming growth factor (TGF-b) pathway (Zhang et al, Cell Stem Cell, 2016), further contributing to BMF. The molecular pathways in FA HSPCs leading to BMF and MDS/AML remain unknown. Although primary HSPCs from BM of FA patients are a useful model system, studying these cells is challenging because of their heterogeneity and low numbers. Sub-populations of HSPCs with heterogeneous transcriptional profiles may co-exist in the BM of FA patients. These subpopulations may include (1) stressed HSPCs sustaining hematopoiesis, (2) HSPCs committed to apoptosis resulting from accumulation of unrepaired DNA damage, and (3) premalignant/malignant cells that eventually lead to clinically detectable MDS or AML. Recently, in order to identify determinants of BMF, we performed single-cell transcriptome profiling of primary HSPCs from FA patients (Rodriguez et al, Cell Stem Cell, 2020). In addition to overexpression of p53 and TGF-b pathway genes, we identified high levels of MYC expression. We correspondingly observed coexistence of distinct HSPC subpopulations expressing high levels of TP53 or MYC in FA bone marrow (BM). MYC-high HSPCs showed significant downregulation of cell adhesion genes, consistent with enhanced egress of FA HSPCs from bone marrow to peripheral blood. We speculate that MYC overexpression impairs HSPC function in FA patients and contributes to exhaustion in FA bone marrow. In my seminar, I will describe the cellular and clinical manifestations of senescence and premature aging in FA patients. Specifically, FA patients exhibit the three major causes of cellular senescence including 1) replicative senescence 2) oncogene-induced senescence (OIS) and 3) stress-induced senescence. Citation Format: Alan D. D'Andrea. Inherited DNA repair defects and premature aging [abstract]. In: Proceedings of the AACR Special Conference: Aging and Cancer; 2022 Nov 17-20; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2022;83(2 Suppl_1):Abstract nr IA002.

Abstract 2222: Detecting clinically significant prostate cancers: Tissue metabolomics refines multiparametric MRI-ultrasound fusion prostate biopsy

Abstract The advent of prostate specific antigen (PSA) testing led to increased early prostate cancer (PCa) detection and has decreased PCa-related death. However, PSA is not cancer-specific, and the challenge persists of differentiating those PCa patients with indolent tumors from those requiring definitive therapy. Metabolomic profiles have the potential to capture molecular dynamics of disease and to reflect disease status before cellular manifestations become observable by histopathology. With clinical, multiparametric magnetic resonance imaging (mpMRI)-positive, fusion biopsy-targeted tissue cores and mpMRI-negative controls in a training-testing cohort design, we studied the potential of magnetic resonance spectroscopy (MRS) to yield cancer metabolomic profiles that could help discriminate likely indolent from clinically significant disease. Using MRS-based PCa metabolomic analyses, performed prior to histology, our approach is able to: determine metabolomic relevations identified in fusion biopsy targets, estimate the scale of PCa metabolomic fields, and detect clinically significant disease in tissues deemed benign or low-risk PCa by pathology and imaging. Our intact tissue MRS metabolomics evaluations indicated significant differences in individual prostate tissue metabolites based on Target-Contralateral (Contral) paired comparisons for both Training and Testing cohorts. We identified metabolomic differences among Target prostate biopsy cores obtained from mpMRI lesions of different PI-RADS scores, and between Target and non-target Contral cores. As a retrospective study, we also analyzed data collected at the time of the initial prostate biopsy alongside patient status across follow up. By introducing metabolomics, as compared with using PSAd or PI-RADS alone, the sensitivity predictions increased by 80.0% and 25.0%, respectively; NPV increased by 18.1% and 8.0%; and accuracy for PSAd increased by 13.0%. PI-RADS accuracy stayed the same Our results show that tissue metabolomic profiles could augment current MR-based imaging findings and histopathological evaluations of fusion biopsies for certain patient populations by more accurately characterizing them into clinically significant or insignificant subgroups. In our analyses, tissue metabolomics alone, or its combination with other clinical parameters, improved sensitivity and negative predictive values, as well as overall accuracy, for our testing cohort. This method, which relies on performing tissue MRS of needle biopsy cores prior to histopathologic analysis, causes no interruption to patient care. Findings from our study demonstrate the utility and translational potential of cancer metabolomics in personalized treatment for PCa and encourages the development of in vivo PCa metabolomic imaging to enhance the diagnostic utility of mpMRI. Citation Format: Leo L. Cheng, Adam S. Feldman, Lindsey A. Vandergrift, Isabella H. Muti, Florian Rumpf, Andrew Gusev, Yannick Berker, Marcella R. Cardoso, Taylor L. Fuss, Emily D. Negroponte, Shulin Wu, Felix Ehret, Christopher A. Dietz, Sarah S. Dinges, Thitinan Chulroek, Edouard Nicaise, Piet Habbel, Martin Ayree, Johannes Nowak, Douglas M. Dahl, Chin-Lee Wu, Mukesh Harisinghani. Detecting clinically significant prostate cancers: Tissue metabolomics refines multiparametric MRI-ultrasound fusion prostate biopsy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2222.

Sickle cell disease as an accelerated aging syndrome.

Sickle cell disease (SCD) is characterized by vaso-occlusion, hemolysis, and systemic manifestations that form the hallmark of the disease. Apart from morbidity, SCD is also associated with increased mortality and decreased quality of life. Aging is a natural phenomenon that is associated with changes at cellular, tissue, and organ levels, in addition to the loss of physical fitness, increased susceptibility to diseases, and a higher likelihood of mortality. Some of the cellular mechanisms involved in normal (or physiological) aging include abnormalities of sphingolipids (ceramides) and reduced length of the telomere. These changes have also been documented in SCD. Cellular, organs, and physical manifestations of SCD resemble an accelerated aging syndrome. Sickle erythrocytes also acquire morphological features similar to that of aged normal erythrocytes and are thus picked up early by the macrophages for destruction. Brain, kidney, heart, innate and adaptive immune system, and musculoskeletal system of patients with SCD exhibit morphological and functional changes that are ordinarily seen in the elderly in the general population. Stroke, silent cerebral infarcts, cardiomegaly, heart failure, pulmonary hypertension, nephropathy with proteinuria, osteopenia, osteoporosis, osteonecrosis, gout, and infections are exceedingly common in SCD. In this review, we have attempted to draw parallels between SCD and accelerated aging syndromes.

αS Oligomers Generated from Interactions with a Polyunsaturated Fatty Acid and a Dopamine Metabolite Differentially Interact with Aβ to Enhance Neurotoxicity.

It is increasingly becoming clear that neurodegenerative diseases are not as discrete as originally thought to be but display significant overlap in histopathological and clinical presentations. For example, nearly half of the patients with Alzheimer's disease (AD) and synucleinopathies such as Parkinson's disease (PD) show symptoms and pathological features of one another. Yet, the molecular events and features that underlie such comorbidities in neurodegenerative diseases remain poorly understood. Here, inspired to uncover the molecular underpinnings of the overlap between AD and PD, we investigated the interactions between amyloid-β (Aβ) and α-synuclein (αS), aggregates of which form the major components of amyloid plaques and Lewy bodies, respectively. Specifically, we focused on αS oligomers generated from the dopamine metabolite called dihydroxyphenylacetaldehyde (DOPAL) and a polyunsaturated fatty acid docosahexaenoic acid (DHA). The two αS oligomers showed structural and conformational differences as confirmed by the disparity in size, secondary structure, susceptibility to proteinase K digestion, and cytotoxicity. More importantly, the two oligomers differentially modulated Aβ aggregation; while both inhibited Aβ aggregation to varying extents, they also induced structurally different Aβ assemblies. Furthermore, Aβ seeded with DHA-derived αS oligomers showed greater toxicity than DOPAL-derived αS oligomers in SH-SY5Y neuroblastoma cells. These results provide insights into the interactions between two amyloid proteins with empirically distinctive biophysical and cellular manifestations, enunciating a basis for potentially ubiquitous cross-amyloid interactions across many neurodegenerative diseases.

Cannabis use, abuse, and withdrawal: Cannabinergic mechanisms, clinical, and preclinical findings.

Cannabis sativa is the most widely used illicit drug in the world. Its main psychoactive component is delta‐9‐tetrahydrocannabinol (THC), one of over 100 phytocannabinoid compounds produced by the cannabis plant. THC is the primary compound that drives cannabis abuse potential and is also used and prescribed medically for therapeutic qualities. Despite its therapeutic potential, a significant subpopulation of frequent cannabis or THC users will develop a drug use syndrome termed cannabis use disorder. Individuals suffering from cannabis use disorder exhibit many of the hallmarks of classical addictions including cravings, tolerance, and withdrawal symptoms. Currently, there are no efficacious treatments for cannabis use disorder or withdrawal symptoms. This makes both clinical and preclinical research on the neurobiological mechanisms of these syndromes ever more pertinent. Indeed, basic research using animal models has provided valuable evidence of the neural molecular and cellular actions of cannabis that mediate its behavioral effects. One of the main components being central action on the cannabinoid type‐one receptor and downstream intracellular signaling related to the endogenous cannabinoid system. Back‐translational studies have provided insight linking preclinical basic and behavioral biology research to better understand symptoms observed at the clinical level. This narrative review aims to summarize major research elucidating the molecular, cellular, and behavioral manifestations of cannabis/THC use that play a role in cannabis use disorder and withdrawal.

COVID-19 как системное заболевание

COVID-19 usually manifests by respiratory symptoms. However, it would be an erroneous simplification to consider it as a local respiratory disease. The nervous system and intestines are often involved even in patients with mild infection, although the risk of dissemination of the infectious process and the development of severe systemic disease is mainly associated with lung damage. The addition of infectious thrombotic microvasculitis (endothelitis) to bronchopneumonia-alveolitis not only forms a substrate for respiratory failure, but also increases a risk of viruses entry into the bloodstream. Viral sepsis develops, whereas inflammatory thrombosis damages new areas of the vascular bed. These mechanisms or direct viral invasion can result in involvement of many tissues and organs in the pathological process. This review examines the molecular, cellular and clinical manifestations and complications of the new coronavirus disease.

Screening of Synthetic Isoxazolone Derivative Role in Alzheimer's Disease: Computational and Pharmacological Approach.

Alzheimer's disease (AD) is age-dependent neurological disorder with progressive loss of cognition and memory. This multifactorial disease is characterized by intracellular neurofibrillary tangles, beta amyloid plaques, neuroinflammation, and increased oxidative stress. The increased cellular manifestations of these markers play a critical role in neurodegeneration and pathogenesis of AD. Therefore, reducing neurodegeneration by decreasing one or more of these markers may provide a potential therapeutic roadmap for the treatment of AD. AD causes a devastating loss of cognition with no conclusive and effective treatment. Many synthetic compound containing isoxazolone nucleus have been reported as neuroprotective agents. The aim of this study was to explore the anti-Alzheimer's potential of a newly synthesized 3,4,5-trimethoxy isoxazolone derivative (TMI) that attenuated the beta amyloid (Aβ1-42) and tau protein levels in streptozotocin (STZ) induced Alzheimer's disease mouse model. Molecular analysis revealed increased beta amyloid (Aβ1-42) protein levels, increased tau protein levels, increased cellular oxidative stress and reduced antioxidant enzymes in STZ exposed mice brains. Furthermore, ELISA and PCR were used to validate the expression of Aβ1-42. Pre-treatment with TMI significantly improved the memory and cognitive behavior along with ameliorated levels of Aβ1-42 proteins. TMI treated mice further showed marked increase in GSH, CAT, SOD levels while decreased levels of acetylcholinesterase inhibitors (AChEI's) and MDA intermediate. The multidimensional nature of isoxazolone derivatives and its versatile affinity towards various targets highpoint its multistep targeting nature. These results indicated the neuroprotective potential of TMI which may be considered for the treatment of neurodegenerative disease specifically in AD.

Molecular and Cellular Manifestations of Biological Aging of Cochlear Inner and Outer Hair Cells

Age-related hearing loss (ARHL) negatively impacts quality of life in the elderly population. The prevalent cause of ARHL is loss of mechanosensitive cochlear hair cells (HCs). The molecular and cellular mechanisms of HC degeneration remain poorly understood. Using RNA-seq transcriptomic analysis of inner and outer HCs isolated from young and aged mice, we show that HC aging is driven by changes in key molecular processes, including transcription, DNA damage/repair, inflammation, autophagy, and oxidative stress, as well as genes related to HC unique morphology and function. At the cellular level, HC aging is characterized by loss of stereocilia, shrinkage of HC soma and reduction in outer HC mechanical properties, suggesting that functional decline in mechanotransduction and cochlear amplification underlie ARHL and precede HC loss. Our study reveals novel molecular and cytological profiles of aging HCs, identifies several biomarkers including Foxo3, Jund and Cbx3, and suggests potential therapeutic targets for ameliorating ARHL.

Nutritional Mediators of Cellular Decline and Mitochondrial Dysfunction in Older Adults

Aging is the primary risk factor for progressive loss of function, onset of disease, and increased vulnerability to negative health-related outcomes. These clinical manifestations arise from a decline in mitochondrial and metabolic processes considered the hallmarks of aging. Collectively, these changes can be defined as age associated cellular decline (AACD) and are often associated with signs and symptoms such as fatigue, reduced strength and low physical activity. This symposium will explore mechanisms, clinical signs, and emerging nutritional interventions for AACD. Dr. Feige’s presentation will serve as an introduction by highlighting mechanisms underlying functional declines in skeletal muscle with aging. He will discuss the Multi-Ethnic Molecular determinants of Sarcopenia (MEMOSA) study, which found impaired mitochondrial bioenergetic capacity in skeletal muscle of older adults with sarcopenia compared to age-matched controls, and identified mitochondrial function as a key target for intervention. Dr. Guralnik will discuss the connection between cellular changes and clinical manifestations of AACD. He will report on an expert consensus study group which developed an initial framework to identify self-reported symptoms and observable signs of AACD in adults over50 years. Lastly, Dr. Singh will discuss the evidence for nutritional interventions to address sources of AACD, focusing on those targeting mitochondrial dysfunction. Recent research on dietary interventions with urolithin A (an activator of mitophagy) and nicotinamide riboside (an NAD+ booster) will be reviewed. Overall, this symposium will highlight key mechanisms and clinical signs of AACD, and the potential for novel nutrition interventions to support cellular function and healthy aging.

SARS-CoV-2 Aiming for the Heart: A Multicenter Italian Perspective About Cardiovascular Issues in COVID-19.

The rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the high fatality rate of coronavirus disease 2019 (COVID-19) have been putting a strain on the world since December 2019. Infected individuals exhibit unpredictable symptoms that tend to worsen if age is advanced, a state of malnutrition persists, or if cardiovascular comorbidities are present. Once transmitted, the virus affects the lungs and in predisposed individuals can elicit a sequela of fatal cardiovascular consequences. We aim to present the pathophysiology of COVID-19, emphasizing the major cellular and clinical manifestations from a cardiological perspective. As a roaming viral particle or more likely via the Trojan horse route, SARS-CoV-2 can access different parts of the body. Cardiovascular features of COVID-19 can count myocardial injuries, vasculitis-like syndromes, and atherothrombotic manifestations. Deviations in the normal electrocardiogram pattern could hide pericardial effusion or cardiac inflammation, and dispersed microthrombi can cause ischemic damages, stroke, or even medullary reflex dysfunctions. Tailored treatment for reduced ejection fraction, arrhythmias, coronary syndromes, macrothrombosis and microthrombosis, and autonomic dysfunctions is mandatory. Confidently, evidence-based therapies for this multifaceted nevertheless purely cardiological COVID-19 will emerge after the global assessment of different approaches.

Bilateral cervical contusion spinal cord injury: A mouse model to evaluate sensorimotor function

Spinal cord injury is a severe condition, resulting in specific neurological symptoms depending on the level of damage. Approximately 60% of spinal cord injuries affect the cervical spinal cord, resulting in complete or incomplete tetraplegia and higher mortality rates than injuries of the thoracic or lumbar region. Although cervical spinal cord injuries frequently occur in humans, there are few clinically relevant models of cervical spinal cord injury. Animal models are critical for examining the cellular and molecular manifestations of human cervical spinal cord injury, which is not feasible in the clinical setting, and to develop therapeutic strategies. There is a limited number of studies using cervical, bilateral contusion SCI and providing a behavioral assessment of motor and sensory functions, which is partly due to the high mortality rate and severe impairment observed in severe cervical SCI models. The goal of this study was to develop a mouse model of cervical contusion injury with moderate severity, resulting in an apparent deficit in front and hindlimb function but still allowing for self-care of the animals. In particular, we aimed to characterize a mouse cervical injury model to be able to use genetic models and a wide range of viral techniques to carry out highly mechanistic studies into the cellular and molecular mechanisms of cervical spinal cord injury. After inducing a bilateral, cervical contusion injury at level C5, we followed the recovery of injured and sham-uninjured animals for eight weeks post-surgery. Hindlimb and forelimb motor functions were significantly impaired immediately after injury, and all mice demonstrated partial improvement over time that remained well below that of uninjured control mice. Mice also displayed a significant loss in their sensory function throughout the testing period. This loss of sensory and motor function manifested as a reduced ability to perform skilled motor tasks in all of the injured mice. Here, we describe a new mouse model of moderate bilateral cervical spinal cord injury that does not lead to mortality and provides a comprehensive assessment of histological and behavioral assessments. This model will be useful in enhancing our mechanistic understanding of cervical spinal cord injury and in the development of treatments targeted at promoting neuroprotection, neuroplasticity, and functional recovery after cervical SCI.

CNDAC-Induced DNA Double-Strand Breaks Cause Aberrant Mitosis Prior to Cell Death.

Incorporation of the clinically active deoxycytidine analogue 2'-C-cyano-2'-deoxy-1-β-D-arabino-pentofuranosyl-cytosine (CNDAC) into DNA generates single-strand breaks that are subsequently converted to double-strand breaks (DSB). Here, we investigated the cellular manifestations of these breaks that link these mechanisms to cell death, and we further tested the relevance of DNA repair pathways in protection of cells against CNDAC damage. The present investigations demonstrate that following exposure to CNDAC and a wash into drug-free medium, chromosomal aberrations, DNA strand breaks, and multinucleate cells arose. These portended loss of viability and were dependent upon exposure time, CNDAC concentration, and passage through mitosis. Following a pulse incubation with CNDAC, live cell imaging using GFP-tagged histone H2B as a marker demonstrated a normal rate of progression to mitosis, but a concentration-dependent delay in passage to a second mitosis. Progression through mitosis was also delayed and accompanied by formation of multinucleate cells. CNDAC-treated cells lacking XPF-ERCC1 nuclease function showed a 16-fold increase in chromosome aberrations. Chromosomal damage in Rad51D-mutant cells (homologous recombination repair deficient) were even more severely affected with extensive aberrations. Rodent or human Polq (POLQ) mutant cells, defective in Pol θ-mediated alternative end joining, did not show enhanced cellular sensitivity to CNDAC. These findings are consistent with formation of DSBs in the second S-phase following exposure, resulting in chromosome aberrations, aberrant mitoses, and subsequent apoptosis.